The Saskatchewan government and a First Nation are at odds over whether an unlicensed cannabis store is illegal. A vendor displays marijuana for sale during the 4-20 annual marijuana celebration in Vancouver on Friday, April 20, 2018.DARRYL DYCK / THE CANADIAN PRESS

REGINA — The Crown agency responsible for overseeing cannabis sales in Saskatchewan has sent a warning letter to a First Nation that has opened an unlicensed pot store.

The Saskatchewan Liquor and Gaming Authority says provincial and federal legislation still applies on reserve land.

It says the Muscowpetung Saulteaux First Nation must have a provincial licence to open a pot store legally.

The letter also says that cannabis for commercial sale needs to be produced by someone with a federal licence to grow it.

The First Nation, northeast of Regina, opened its cannabis store last week.

Chief Anthony Cappo has said the First Nation has a sovereign right to make its own cannabis rules.

The Federation of Sovereign Indigenous Nations is supporting the First Nation in exercising what it says are its inherent and treaty rights.